This invention pertains to the field of N-aryl-N-(4-piperidinyl)-arylacetamides. In the prior art there may be found some N-aryl-N-(4-piperidinyl)amides having pharmacological, e.g., analgesic, properties. A number of such compounds may be found in the following references:
U.S. Pat. No. 2,748,134; PA1 U.S. Pat. No. 3,869,463; PA1 U.S. Pat. No. 3,164,600; PA1 C.A., 78, 147752r (1973); and PA1 C.A., 77, 34349a (1972). PA1 Ar is a member selected from the group consisting of phenyl, mono- and di-substituted phenyl, pyridinyl and 2-pyrimidinyl, wherein each substituent in said mono- and di-substituted phenyl is independently selected from the group consisting of halo and lower alkyl; PA1 Ar.sup.1 is a member selected from the group consisting of phenyl, mono- and di-substituted phenyl, and thienyl, wherein each substituent in said mono- and di-substituted phenyl is independently selected from the group consisting of halo, lower alkyl, hydroxy and lower alkyloxy; and PA1 X is a member selected from the group consisting of hydrogen, lower alkyloxycarbonyl and lower alkyloxymethyl. PA1 0: no effect. PA1 +: decrease of the number of premature beats and increase of the number of normal beats by at least 30% as compared to the control value. PA1 ++: decrease of the number of premature beats and increase of the number of normal beats by at least 50% as compared to the control value. PA1 +++: normalisation of cardial rhythm or decrease of the number of premature beats and increase of the number of normal beats by at least 75% as compared to the control value.
Among other points of difference the anti-arrhythmic compounds of this invention differ from such known compounds by the nature of the arylacetamide group attached to the 4-position of the piperidine nucleus.